Measurement Specialties PC-CARD-DAS16/12AO manual Specifications, Analog input, Accuracy

Chapter 5

Specifications

Typical for 25 °C unless otherwise specified.

Specifications in italic text are guaranteed by design.

Analog input

	Table 1. Analog input specifications
A/D converter type		ADS7804
Resolution		12 bits
Number of channels		16 single-ended / 8 differential, software selectable
Input ranges		±10 V, ±5 V, ±2.5 V, ±1.25 V, 0 to 10 V, 0 to 5 V, 0 to 2.5 V, 0 to 1.25 V,
		software programmable
A/D pacing		Internal counter - 82C54.
(software programmable)		External source - A/D External Pacer,
		software programmable for rising or falling edge
		Software polled
A/D trigger sources		External edge trigger (A/D External Trigger)
A/D triggering modes		Rising or falling edge trigger - software selectable
A/D gate sources		A/D External Trigger, gate high or low, software selectable
		A/D Pacer Gate, gate high
Burst mode		Software selectable option, burst rate = 100 kHz
Data transfer		From 4k sample FIFO via REPINSW
		Programmed I/O
A/D conversion time		10 µs max
Calibrated throughput		100 kHz
Calibration		Auto-calibration, calibration factors for each range stored on
		board in nonvolatile RAM

Accuracy

Accuracies are listed for a 100 kHz sampling rate, single channel operation, a 60 minute warm-up, and operational temperatures within ±2 °C of internal calibration temperature. The calibrator test source high side is tied to Channel 0 In and the low side tied to AGND.

	Table 2. Absolute accuracy specifications
Range		Absolute Accuracy
±10.00 V		±3 LSB max
±5.000 V		±3 LSB max
±2.500 V		±3 LSB max
±1.250 V		±3 LSB max
0 to 10.00 V		±3 LSB max
0 to 5.000 V		±3 LSB max
0 to 2.500 V		±3 LSB max
0 to 1.250 V		±3 LSB max

Each PC-CARD-DAS16/12AO is tested at the factory to assure the board’s overall error does not exceed accuracy limits described in Table 2.

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